Around 50 people protested outside Holyrood, with some holding photos of family members.
They have been supported by Scottish Labour's health and social care spokeswoman Monica Lennon, who is calling for relatives to be allowed more access to care facilities.
Since August 10, up to three visitors from two households have been able to see care home residents in outdoor meetings.
Indoor visits are also now allowed in restricted circumstances, where the care home meets certain conditions including weekly coronavirus testing of staff and a risk assessment approved by the local director of public health.
But campaigners say relatives have been prevented from providing an essential caring role for family members in care homes since the lockdown restrictions were imposed.
Cathie Russell, of the campaign group Care Home Relatives Scotland, told Good Morning Scotland she had seen a “huge decline” in her mother’s cognitive abilities since visiting had been restricted.
She said her mother was in a good home and well cared for but added: “These people have basically been imprisoned since March and their mental health is declining.
"They are completely bewildered, they haven't seen relatives for months and they are having to sit miles away from them when they do."
Ms Lennon said: "Six months since the ban on care home visiting was first introduced, the Scottish Government is still failing to recognise that husbands, wives, children and grandchildren are not simply visitors, they are caregivers and their loved ones are suffering mentally, emotionally and physically the longer contact is prevented or severely restricted.
"Older and disabled people living in care homes cannot be expected to live their lives in isolation without the companionship and affection of their closest family and friends.
"After making terrible decisions at the start of the pandemic, including sending older people into care homes without testing for the virus and limiting their access to healthcare, the Scottish Government's caution is understandable but it is not proportionate.
"Car park visits and waves at the window are falling short of the contact and care that older and disabled people in care homes need.
"Scottish Labour has previously put forward proposals for family caregivers to be given access to routine testing and PPE and afforded the same status as care staff."
A Scottish Government spokeswoman said: "We recognise how hugely important it is for care home residents and loved ones to see each other. But it is complex to balance making this happen safely for everyone against the risks of harm from the virus.
"This balance becomes even more important and challenging when community prevalence of Covid-19 increases, as we have seen in recent days and weeks.
"Indoor visits can resume once care homes have had approval by the local director of public health that their plans have met all safety considerations.
"The intention is to open up further visiting options as soon as it is safe to do so and we will, at all times, keep national guidance under regular review."